Azure Application Gateway is a REGIONAL web traffic load balancer that enables you to manage traffic to your web applications.
Application Gateway routes traffic to a pool of web servers based on the URL of a request
Traditional load balancers operate at the transport layer (OSI layer 4 - TCP and UDP) and route traffic based on source IP address and port, to a destination IP address and port.
Application Gateway can make routing decisions based on additional attributes of an HTTP request, for example URI path or host headers.

Deployment of an Azure Application Gateway requires a dedicated subnet
Azure Application Gateway offers a web application firewall (WAF) that provides centralized protection of your web applications from common exploits and vulnerabilities.
- Web applications are increasingly targeted by malicious attacks that exploit commonly known vulnerabilities.
- SQL injection and cross-site scripting are among the most common attacks.
Application Gateway operates as an application delivery controller (ADC).
- It offers Secure Sockets Layer (SSL) termination, cookie-based session affinity, round- robin load distribution, content-based routing, ability to host multiple websites, and security enhancements.

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Load Balancing

Understand Azure load balancing - Pay attention to the global vs regional use and the type of traffic.
The following table summarizes the Azure load balancing services by these categories:

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SSL Termination

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